This is the temperature of the air inside a tunnel, trough or channel.

Symbol
$\theta_{at}$
Unit
$^{\circ}$C
Formulae
 $iteration$ in tunnel $\lambda_{t} \left(\Delta \theta_{air} + \theta_{at_{0}}\right) + \theta_{at_{i}} \left(1 - \lambda_{t}\right)$ in trough or channel
Related
$\Delta \theta_{air}$
$\theta_{at_{0}}$
$\theta_{at_{i}}$
Used in
$I_{c}$
$k_{air}$
$\nu_{air}$
$p_{atm}$
$\mathrm{Pr}_{air}$
$T_{sa}$
$\theta_{c}$
$\theta_{de}$
$\theta_{hs}$
$\theta_{tm}$
$W_{hs}$